Solve for $x$ and $y$ using substitution. ${-3x-4y = -2}$ ${x = -2y+4}$
Explanation: Since $x$ has already been solved for, substitute $-2y+4$ for $x$ in the first equation. ${-3}{(-2y+4)}{- 4y = -2}$ Simplify and solve for $y$ $6y-12 - 4y = -2$ $2y-12 = -2$ $2y-12{+12} = -2{+12}$ $2y = 10$ $\dfrac{2y}{{2}} = \dfrac{10}{{2}}$ ${y = 5}$ Now that you know ${y = 5}$ , plug it back into $\thinspace {x = -2y+4}\thinspace$ to find $x$ ${x = -2}{(5)}{ + 4}$ $x = -10 + 4$ ${x = -6}$ You can also plug ${y = 5}$ into $\thinspace {-3x-4y = -2}\thinspace$ and get the same answer for $x$ : ${-3x - 4}{(5)}{= -2}$ ${x = -6}$